Stealth Cancer Fighters

Nanoparticles disquised as red blood cells deliver cancer fighting medicines

(RxWiki News) This sounds like something you'd read in a science fiction novel - create a medicine-carrying particle that the body thinks is one of its own. It's a kind of medical stealth technology, and it's here now.

Scientists have devised a way to disguise nanoparticles as red blood cells. The body doesn't know the difference, so these virus-sized high-tech particles can deliver cancer- fighing drugs straight to the tumor.

"Nanoparticles are becoming like stealth bombers to kill cancer."

Here's how it works: The membranes from red blood cells are collected and then used to wrap around and camouflage the biodegradable particles that are filled with drugs.

Liangfang Zhang, a nanoeningeering professor at the University of California San Diego Jacobs School of Engineering and Moores UCSD Cancer Center, says this is the first time a natural membrane has been combined with these synthetic nanoparticles to deliver drugs right where they're needed.

For years, researchers have been working to find ways to mimic the body's own systems and natural behavior as a means of getting drugs where they need to go. But the problem has been that the body's immune system attacks the foreign invaders.

This new technology tricks the body into thinking the nanoparticles are red blood cells so they can live and circulate in the body for long periods of time.

Nanoparticles coated in synthetic materials are currently being used to deliver chemotherapy drugs. However, these particles only circulate for hours, while the special natural coating Zhang is working with allows the stealth fighters to stay in the system for days.

As such, this work which is being funded by a National Institutes of Health (NIH) grant, has leapfrogged the science. Zhang says his team approached the problem from an engineering point of view to bypass fundamental biological challenges to make the particles look and behave like red blood cells.

This new approach could save a patients hours of waiting while chemotherapy drugs are delivered drip by drip intravenously.

Zhang says this "breakthrough" as he characterizes it, could create true personalized medicine. The patient's own blood could be used to harvest the membrane to disquise the nanoparticles.

Future work will focus on finding ways to manufacture the particles for clinical use. Zhang also wants to develop ways to add targeting molecules that will allow the nanonparticles to zero in on and bind with the cancer cells. The team is also working to find ways to load multiple drugs into the nanoparticles.

All these developments, Zhang says, will enable the nanoparticles to target the cancer cells so a whole cocktail of the drugs can be dropped like a bomb into the cancer cells.

Science fiction no more.

Findings from this study are going to be published in the online Early Edition of the Proceedings of the National Academy of Sciences.

Review Date: 
June 23, 2011